Manometric gage.



No; 723,040. V PATENTED MAR.17, 190's 0. SGHMITZ. MANOMETRIG GAGE: APPLIOATION FILE]? D110. 2; 1901.

J [spams-$112M: 2.

NO MODEL,

A Trap/writ FFICE.

lONS'lANZ SCHMITZ, OF BERLIN, GERMANY.

MANOMETRIC GAGE.

SPECIFICATION forming part of Letters Patentlfio. 723,040, dated March 17, 1903. Application filed December 2, 1901. Serial No. 84,337. (No model.)

To all whom, it may concern.-

Be it known that I, ,OoNsTANz SCHMITZ, engineer, a subject of the King of Prussia, German Emperor, residing at 5 Calvin street, Berlin, N. W., German Empire, have invented certain new and useful Improvements in LiquidLevel Indicators, of which the following is a specification.

For gaging the height of a liquid-level it was usual heretofore to indicate the level of the liquidcontained in a receptacle by means of a glass gage or by transmitting the pressure caused by the liquid itself to a mano' metric gage. In the first case when the receptacle is under pressure-as, for instance,

in steam-generators-there is always the I danger that the glass may burst or the passages may become obstructed, so that the device gives wrong indications. In thesecond case the instruments give correct indications as long as water is used; but as soon as the specific gravity of the liquid changes the graduation of the manometric indicating the height and being meant for water only does not correspond with the actual level ofthe liquid. In order to render the indications in such instruments independent of the inner pressure of the receptacle and of the spe- -cific gravity of the liquid the level of which is to be measured, the height of the liquid is to be determined by the pressure of a liquid column, which is inclosed in a suitable appliance, and thus rendered invariable. For this purpose liquids such as oil, alcohol, mercury, or the like are used.

The invention is illustrated in the accompanying drawings, in which similar letters K, being under steam-pressure, can be gaged.

On the water-surface floats a hollow receptacle g, of metal, for instance, and suliiciently' strong to stand the pressure and which has attached to'it a narrow flexible tube a, passing through thewall of the boiler and connectedto the lower space a, of a pressuretransmitting apparatus A. The space a, the

tube 1:, and part of the hollow float g are so that the pressure in the receptacle a exactly corresponds to the height it of the inclosed liquid column. The second tube It may also be arranged in the interior of the tube t',as shown in Fig. 2. In order to allow of filling the float with such liquids as will boil at the temperature of the surrounding hot liquitls-as, for'instance, in steamboilers-theliquid is introduced in a continuous current from the side into the bottom part of the-tube i, Fig. 2. The inner tube 7c extends into the float only to such height as corresponds to the level it is desired to main tain therein, so that it will act as an overflow for the liquid'int-roduced through this tube 76, and thus the liquidcolumn will never rise beyond the overflow-tube. Owing to thefact that fresh liquid is continuously introduced in sufficient quantities the same is prevented from boiling within the interior of the apparatus, thus always maintaining atmospheric pressure within the latter. The pressure is transmitted by a diaphragm to the upperspace b of the receptacle A, which is filled with air or similar fluid. By this medium the pressure is transmitted through a tube e to a manometric gage M, the graduation of the latter being such that variations of ti. water-level between the limits of H are indicated. 0 is an enlargement underneath the manometric 'gage and which by a diaphragm adjustable by a screw (1 can be increased ordecreased, whereby small corrections in the indication of the manometric may be effected.

Fig. 3 shows another modification to be employed, for instance, for liquids with a variable specific gravity in open tanks. On the surface of a liquid of this kind the height of which is to be gaged floats a receptacle g,which is open on the top and made of suitable materiaL-such as glass, metal, stone, or the like and which is preferably of a flat dish shape. On its bottom a flexible tube or a hose is attached, being connected to a pressure-transmitter A, which may be placed outside the tankB. This apparatus consists of two parts a and b, which are separated by a flexible dihphragm, with the lower part a of which the float g is connected by the tube t. The space a, tube 1', and 'spaceg are filled with one of the liquidsmentioned'above as, for instance, alcohol-so that this liquid is nearly at the samelevelas theliquid in BL To the top space b of the receptacle A a narrow tube 6 is attached, leading to'a manometricvgage M The pressure MA is transmitted to M by air but this mayalso be done by means of a liq uid-as, for instance, oil, alcohol, or theIlike. c is an adjusting apparatus, in which the diaphragm can be adjusted by a screw-bolt,d. By this means the air or-liquid inclosed in c is compressed ordis't'e'nded. so that in this way small corrections in the indication of the manometer may be made.

The-apparatus works in the following manner: If the liquid-level in B changes, the float g rises or. descends, and the liquid column it increases or decreases. -In consequence thereofthe pressure upon the-diaphragm in A-increases or decreases, and the manometer indicates the variation of the height H. The graduation ofthe manometer is such that'in ing unchanged, will in consequence thereof eachposition of the float the corresponding height may be read directly on the gage. If the specific gravity of the liquid in B is changedmhe float, all other conditions remaindip more, or less into the liquid. By making the weight of the float g', with the tube 0} and ts contents, assmall and, on the other'ha'nd, the cross-section of the floatsubmerging as large as possible it is possible to reduce the d-iiferences ot the depth to which the float dips intathe liquid to such a degree that the deviations of the indications of the mano-' metric gage from the} actual proper heights H, caused. by difierent specific gravities of the liquid contained in B, are ofsubstantially no account. .T-heindications of the manomstar, as well asthe actual liquid-levels, can be I What I claim, and desire to secure by Letters Patent of the United States, is-

1. A device for indicatingthe height of liquids comprising the combination with. a

suitable container for said liquids, a float and a flexible tube disposed in said container and adapted to receive a column of liquid, and

means connected to said tube and float for:

indicating the height of the said column of liquid. v

2. A device for indicating the height of liquids, comprising a suitable container for diaphragm and a gage operatively connected to said diaphragm, and tubular connections between said gage and said hollow float, and adapted to contain a liquid column.

3. Thecombination with a diaphragm-charm andflregister, and another tube connected with the float above the levelof liquid to be contained therein;

a diaphragm-chamber, another'diaphragmn-icating with the float and the phragm-chamber.

In witness whereof I have hereunto'si'g'ned' myname in the presene;.o witnesses. q/ 61;?"

' I CONSTANZ SCHMITZ.

Witnesses-z HENRY HASPER,

portrayed by gradu'atigns in a well-known I manner.-

WOLDEMAR HAUr'r.

6. The combination of a manometerhavingl s chamber operatively connected therewith, a chambered float, and a flexible tnbecommu i second diathe liquid, a hollow float insaid container, a 

